Health Risk Assessment for Human Exposure to Trace Metals Via Bushmeat in Ghana.

Consumption and trade in bushmeat are entrenched in sub-Saharan Africa amid growing land degradation and environmental pollution that raise safety concerns, yet sustainability of bushmeat extraction and zoonoses considerations have been the focus of bushmeat research. Here, we evaluated the health risk of trace metals in the skeletal muscle, bone, liver, and skin of the black duiker (Cephalophus niger), brush-tailed porcupine (Atherurus africanus), bushbuck (Tragelaphus scriptus), cane rat (Thryonomys swinderianus), and Maxwell's duiker (Cephalophus maxwelli) being the five most hunted and consumed species of bushmeat in Ghana. Sample tissues of the five species were analyzed for Cu, Zn, Se, Cd, As, Pb, and Hg. Targeted hazard quotient (THQ) of Se for black duiker, bushback, and Maxwell's duiker as well as that of Pb for black duiker, Brush-tailed porcupine, and Maxwell's duiker were concerning (> 1) for individuals foraging daily on bushmeat. Thus, cane rat was the only species that recorded both estimated daily intake (EDI) and THQ of Se and Pb within safe limits for daily consumption. In respect of Cu, Zn, Cd, As, and Hg, EDI and THQ values indicated no perceived risk to consumers for all five species. Lifetime cancer risk (CR) of As was negligible for all species. At the rate of bushmeat consumption in sub-Saharan Africa (0.104 kg per day), the cane rat was the only species considered safe for daily consumption among the five species.

Risk of heavy metal ingestion from the consumption of two commercially valuable species of fish from the fresh and coastal waters of Ghana.

BACKGROUND: The need to evaluate the human health safety of fishery resources remain urgent in the mist of the ever-increasing fear of heavy metal toxicity from the consumption of Ghana's fisheries resource, as a consequence of pollution from several anthropogenic activities including artisanal gold mining. Nevertheless, the bigeye grunt (Brachydeuterus auritus) and Bagrid catfish (Chrysichthys nigrodigitatus) remain commercially valuable fish species in West Africa and continue to attract high patronage. METHOD: Forty-five specimens each of C. nigrodigitatus and B. auritus collected from the Weija Dam and the Tema Fishing Habour in Ghana, between June and September 2016, were analysed for seven heavy metals using Atomic Absorption Spectrometry. RESULT: Lead and Cadmium were below detection in all samples while Cu was not detected in B. auritus. Levels of the remaining metals (mg kg-1) were below FAO/WHO maximum permissible limits in fish and occurred in the rank order Se (3.5) > Zn (2.34) > Cu (0.59) > As (0.37) > Hg (0.19) in C. nigrodigitatus and Se (2.97) > Zn (2.28) > Hg (0.31) > As (0.21) in B. auritus. Only As in C. nigrodigitatus recorded Estimated Weekly Intake (EWI) greater than FAO/WHO Provisional Tolerable Weekly Intake (PTWI). Also, As in C. nigrodigitatus and Hg in B. auritus had Targeted Hazard Quotient (THQ) greater than 1 for individuals consuming the fishes on daily basis and therefore, raising concerns. However, for both species of fish, cancer risk of As was 1 in 10,000,000,000 and modified Health Benefits values of Se (HBVSe) were positive indicating the health risks that might accompany Hg exposure would be negated. Since toxicity depends on the concentration and quantity of a pollutant consumed, safe maximum consumption rate of C. nigrodigitatus based on As concentrations was 0.21 mg per day and that of B. auritus was 0.058 mg per day for Hg. With an average of 0.227 kg fish per meal of an adult human, these translated into not more than 24 C. nigrodigitatus and nine (9) B. auritus meals in a month but because fish is consumed at 0.0685 kg per person per day in Ghana, these values respectively translates to 93 and 30 safe days of consumption per month. CONCLUSION: At the rate of 0.0685 kg fish per person per day that fish is consumed in Ghana, the consumption of the two species of fish in Ghana would essentially be of little or no consequence to consumers.